Sara Paxton doesn't wear a bathing suit top any time she is in her mermaid form
A girl wears a shirt over her one piece bathing suit
A girl takes her top off a bathing suit top is underneath.
Claire reveals to Aquamarine and Hailey that "all" the girls are after Raymond. Even "a few boys".
Very mild
Young men and women wear swimsuits in many beach scenes and young women wear low-cut tops that reveal cleavage in several scenes.
A mermaid's long hair hangs over her chest covering her breasts and her bare back to the waist is seen several times.
A young girl, presumably naked--her hair covering her breasts, is hiding behind objects while conversing with two other girls (a couple very quick glimpses of one of her breasts can be seen as her hair moves--her nipple is covered by an aquamarine-colored pastie). She also turns around to show the two girls her bare buttocks, and says "Isn't it cute?" (we only see her bare back and shoulders).
A girl asks a mermaid if she can make, "boobs come out of hiding."
A girl wears a blue shirt made to look like a dress presumably with no underwear (a couple quick glimpses up her dress are seen, and are digitally altered to look like she's not wearing anything).